Medication management systems comprising dispensing stations have been known for a number of years, and by way of example, a form of a such system is described in U.S. Pat. No. 6,021,392, the entire contents of which are incorporated by reference herein. Dispensing stations or stations are typically used by healthcare institutions to efficiently store, track, and document the usage of drugs and related items. In addition to tracking drug and device quantities, dispensing stations track patient information as well as expiration dates and lot numbers of items stored within them. Functioning as mobile satellites of a pharmacy, the dispensing stations are often located at numerous points throughout a facility in order to provide authorized users, such as nurses, doctors, and other caregivers controlled and convenient access to drugs and supplies.
Items are typically stored in dispensing station drawers which may be locked depending on the nature of the items inside. Dispensing drawers may be further partitioned into a number of sections or containers within each drawer. For example, such partitions may result in drawer containers that are consecutive with one another along the sliding direction of the drawer. Graduated access to containers toward the rear of such drawers has been controlled by limiting the extent to which an unlocked drawer may slide out of its cabinet.
Alternatively, drawers have comprised a number of modular, individually removable containers of varying size that can be locked down onto the floor of drawer. The modules can have separate lockable lids, allowing the modules to be filled with items at a location remote from the dispensing station, such as in a pharmacy, and later installed in the dispensing station drawer. Unlocking of drawers and individual container lids at the dispensing station is typically handled by a control unit having a user interface, such as a keyboard and/or touch sensitive display screen mounted on the dispensing station. A user interacts with the interface to select the item he or she wishes to access. The interface also cooperates with a processor to provide electrical signals to open or unlock the selected drawer or lid so that the user may take the selected medication or item for administration to a patient.
Prior dispensing stations have allowed the user to search for and obtain a particular item by entering a personal identifier and password (i.e., logging on), and then scrolling through a pick list of available items shown on a display screen or by inputting the name of the item using a keyboard. Where the item is available and the user is recognized as having the proper authority, a drawer number and container number are indicated on the display screen and, if necessary, the control unit unlocks the corresponding drawer. Alternatively, illuminated lights on the drawer have been used to indicate the location of the appropriate container. When the drawer is closed, the control unit records the time of the transaction, item description, quantity taken, name of the user, etc. In prior art systems, the transaction record relies upon the user removing the correct item from the correct container. Although the user may later recognize that the wrong item was removed, the user must perform an additional transaction to return the item to the drawer.
Management of medication during anesthesia presents unique challenges. Because anesthesia involves the use of controlled, narcotic medications, healthcare institutions must implement strict documentation and record keeping of usage to avoid substantial monetary fines and the possible loss of accreditation. Automated management processes and systems in anesthesia are well known, an example of which is found in U.S. Pat. No. 6,339,732, which is incorporated in its entirety by reference herein.
In general, most items and medications to used during surgery are taken from anesthesia dispensing stations in advance of the surgical procedure. The anesthesiologist administers medication based on the present condition of the patient and must be able to readily obtain and administer additional quantities or current medications as well as additional medications as needed to respond to unforeseen or changing circumstances during surgery while adhering to the institution's strict record keeping and control procedures. Accordingly, the drawers of the dispensing station in a surgical suite are typically kept open or unlocked during a surgical procedure to provide ready access to the stored medications by the anesthesiologist. Since the items stored in the dispensing station drawers are often in plain view, the location of many of the items is known in advance by the anesthesiologist. As such, it is inefficient to require the anesthesiologist to pre-select or identify an item through the use of a keyboard or pick list as is done in prior art systems because such a process requires time that may not be available when the anesthesiologist needs a particular medication to respond to a rapidly developing or changing situation. Furthermore, when several items are dispensed in response to an unexpected situation, identification of the items through a keyboard or pick list is prone to human error and is likely to be deferred until a later, more convenient time. At such a later time, it is not unusual for some details of the transaction to have been forgotten.
Many items stored in dispensing stations, such as general supplies, are of a type that requires little or no control, are varied in size, and are often packaged together in packs customized for a type of situation or surgical procedure, such as, for example, pediatric, cardiac and neurological procedures. In addition, some items are used more frequently than others and thus may require greater quantities to be stocked within the dispensing station. To address this need, attempts have been made to make drawers in dispensing stations configurable by the user. For instance, drawers have been divided into zones with partitions between each zone being removable to create containers of variable size comprising one or more zones. A limiting factor with configurable drawers is that the means for informing the user of the location of a container holding a desired item must adapt to changing drawer configurations. One prior solution to this problem involved mounting a light adjacent each zone and then illuminating certain of the lights to inform the user of the container from which an item was removed. When that container encompasses five zones, for example, the five lights adjacent the five zones may be illuminated to indicate the location of the appropriate container.
Another disadvantage of configurable drawers is that the means of controlling and tracking access to an item must adapt to changing container configurations. One prior solution to this problem mounted a “take” switch adjacent each zone in the drawer. When removing an item from the drawer, the user is required to actuate the take switch a multiple of times corresponding to the quantity removed from the corresponding container. A “cancel” switch is employed to cancel or indicate a quantity returned to the drawer. For example, when a container encompasses ten zones, the user removing medication may be required to actuate one of the ten take switches adjacent the ten zones.
The cost of a dispensing station typically increases with the number of lights and switches on any given drawer. The amount of electrical wiring and components subject to wear or malfunction also increases with the number of lights and switches. Moreover, without a quick and convenient means of verification, tracking errors are more likely to occur when a user, distracted by the pressure of a sudden and unforeseen event, takes an item from the wrong container, presses the wrong switch on the drawer, or presses the switch an incorrect number of times.
As mentioned above, some prior art dispensing stations control the extent to which its drawer slides open in order to prevent access to containers in the rear of the drawer. A configurable drawer may have multiple longitudinal columns of containers with each column having independently movable transverse partitions, which can result in an irregular pattern of partitions. For example, a drawer may have to slide out eight inches in order to allow access to the second container in one column, but the drawer may have to slide out eleven inches in order to allow access to the second container in another column. Thus, having configurable drawers may be disadvantageous in that the control unit on the dispensing station must adapt to irregular drawer configurations. Moreover, a user may be unlikely to reconfigure a drawer if it requires complicated or time consuming reprogramming of the control unit.
Accordingly, those skilled in the art have recognized a need for a system and method for storing items and tracking item usage that provide greater flexibility and ease in reconfiguring the number, size, and location of containers in storage drawers of a medication dispensing cabinet while reducing the potential for tracking errors to occur. The present invention satisfies these and other needs.